V2X RF front end module assistance circuits: Observation receiver, DPD, and supply modulator

In today's connectivity ecosystem, the connection of not only mobile devices but also pedestrians, traffic infrastructures, ground stations and autonomous vehicles, with each other and with the environment, is growing. In this proposed example work, an observation receiver operating in the n47 frequency band (5855-5925 MHz), a digital pre-distorter (DPD), and a 40 MHz bandwidth supply modulator are pre¬sented for vehicle-to-everything (V2X) connectivity. These assistant blocks are located on the same die as the RF power amplifier. According to the simulations, the observation receiver has a maximum bandwidth of 120 MHz, which can implement DPD in systems using 5G NR signals with a bandwidth of 10/20/30/40 MHz. The low-IF architecture receiver transmits the very high swing signal from the PA output to the data converter with the help of a programmable attenuator. LUT-based DPD is a hard-coded IP with third-order memory. The supply modulator, which can provide 2 A current up to 5 V output voltage, has over 85% efficiency for 5G NR signals with 8 dB PAPR.